A PurpleAir and a PurpleAir Flex air quality monitoring sensor was installed at a monitoring site in East Hartford, Connecticut to evaluate the sensors performance tracking PM2.5 data. PurpleAir data was corrected using the extended U.S-wide correction equation developed by the EPA to reduce bias in sensor data (more information found here: AirNow). Hourly data from 2023 was then compared to a T640 reference monitor located at the same location. The full dataset used can be downloaded here Download CSV.

Sensor Details

PurpleAir Specifications

Sensor Type Possible Configuration Evaluated Configuration Cost Data Access Power Supply Considerations Reference Monitor Compared
PurpleAir
PurpleAir Flex

Setup

photos here


Timeseries Comparison

PurpleAir and PurpleAir Flex hourly data for PM 2.5, temperature and relative humidity were compared by quarter to reference values (Q1: January-March, Q2: April-June, Q3: July-September, Q4: October-December).

PM2.5

Quarter 1

Quarter 2

Quarter 3

Quarter 4

Temperature

Quarter 1

Quarter 2

Quarter 3

Quarter 4

Relative Humidity

Quarter 1

Quarter 2

Quarter 3

Quarter 4

Correlation Comparison

Purple Air and Reference Correlation

PM2.5

Temperature

Relative Humidity

Purple Air Flex and Reference Correlation

PM2.5

Temperature

Relative Humidity

Purple Air and Purple Air Flex

PM2.5

Temperature

Relative Humidity

Results Summary